Detection and monitoring system for the management of combined sewer systems

ABSTRACT

A combined sewer/enclosure overflow (CSO) sensor system is described for accurate detection and measurement of overflow events. From the combined data, trending information can determine if there is debris accumulation. Rain masks can be used in the trending data to measure overall health. External sensors in combination with the CSO sensors provide predictive information and additional levels of information/data accuracy. The sensor system automatically and remotely monitors CSO locations and provides real-time data regarding start times, stop times, duration, and flow volumes of overflows that occur in these structures and provide regulatory and public notification of these events.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This patent application is a continuation of and claims priority to U.S.patent application Ser. No. 16/836,838, filed Mar. 31, 2020, which is acontinuation of U.S. patent application Ser. No. 15/716,751, filed Sep.27, 2017, now U.S. Pat. No. 10,612,228, issued on Apr. 7, 2020, entitledDETECTION AND MONITORING SYSTEM FOR THE MANAGEMENT OF COMBINED SEWERSYSTEMS, which claims priority to U.S. provisional patent application62/400,574, filed Sep. 27, 2016, the contents of which are herebyincorporated by reference in their entirety.

FIELD

This invention is related to underground structures or enclosures. Moreparticularly, this invention is directed to intelligent monitoring ofcombined overflow system (COS) structures.

BACKGROUND

Combined sewers operate by using a conveyance that allows for commonflows of septic sewage and storm water. Under most conditions this flowis treated by a wastewater treatment plant that then discharges torivers or the ocean or is reclaimed for reuse. If storm driven,aggressive flows results, and this increased volume of water cannot beprocessed by the treatment plant and therefore must be dischargeduntreated into the natural environment. Unavoidable contamination of theenvironment occurs. Current monitoring methods for combined sewersystems are often primitive, poorly designed, or poorly deployed.

In view of the deficiencies of the current methodologies, varioussystems and methods are described that provide more accurate andcomprehensive methods) for determining the start, end, and volume ofsewage discharged to allow better planning and response for combinedsewer operations.

SUMMARY

The following presents a simplified summary in order to provide a basicunderstanding of some aspects of the claimed subject matter. Thissummary is not an extensive overview, and is not intended to identifykey/critical elements or to delineate the scope of the claimed subjectmatter. Its purpose is to present some concepts in a simplified form asa prelude to the more detailed description that is presented later.

In one aspect of the disclosed embodiments, a combined overflowstructure (COS) detection system is provided, comprising: an overflowstructure containing a non-overflow side, a weir, and an overflow side;a first sensor positioned over the overflow structure to determine afluid level of the non-overflow side; a second sensor positioned overthe overflow structure to determine a fluid level over a top of a weir;sensor supporting electronics above the overflow structure coupled tothe first and second sensors; a wireless transmitter coupled to thesensor supporting electronics; and an antenna coupled to the wirelesstransmitter, wherein data from these sensors is wirelessly transmittedto a central data processing system, and the sensor data is used toestablish a start and end time of an overflow event and to determine avolume of fluid discharged over the weir.

In another aspect of the disclosed embodiments, the above system isprovided, further comprising a third sensor over the overflow structurepositioned to determine a fluid level of the overflow side and coupledto the sensor supporting electronics; and/or wherein the overflowstructure is in a sewer system; and/or wherein the overflow structure isin a manhole; and/or wherein one or more of the sensors are eitherultrasonic, radar, capacitive, optical, standoff water level, immersedwater level, weir trigger level, contact, float, moisture, conductivitysensor, magnetic, or micro-electro-mechanical (MEM); and/or where thesecond sensor is affixed to the top of the weir and comprises aplurality of weir sensor structures disposed across the top of the weir,the plurality providing at least one of level and flow data, andmitigating against data inaccuracy from individual sensor fouling in theweir sensor structures; and/or wherein the weir sensor structure is inan inverted U-shape and contains a liquid or conductive sensor therein;and/or wherein the weir sensor structure contains a MEM sensor with amovable float; and/or within the MEM sensor is attached to the weirsensor structure via a swivel or rotating connector; and/or wherein thecentral data processing system determines fluid level trendinginformation; and/or where the fluid level trending information isdeterminative of an obstruction in the overflow structure; and/orfurther comprising a rain mask over the fluid level trending informationto remove rain effects; and/or further comprising one or moreenvironmental sensors external to an enclosure housing the overflowstructure, the environmental sensors also forwarding its data to thecentral data processing system; and/or wherein a sampling rate of thesensors is variable and altered depending on a level detection thresholdor an external trigger.

In another aspect of the disclosed embodiments, a method for overflowdetection in an overflow structure (COS) is provided, comprising:positioning a first sensor over an overflow structure to determine afluid level of a non-overflow side of the overflow structure;positioning a second sensor over the overflow structure to determine afluid level over a top of a weir in the overflow structure; couplingsensor supporting electronics above the overflow structure to the firstand second sensors; coupling a wireless transmitter to the sensorsupporting electronics; coupling an antenna to the wireless transmitter;transmitting the sensor data to a central data processing system; andestablishing a start and end time of an overflow event and determining avolume of fluid discharged over the weir from data received from thesensors.

In yet another aspect of the disclosed embodiments, the above method isprovided, further comprising: positioning a third sensor over theoverflow structure to determine a fluid level of the overflow side; andcoupling the third sensor to the sensor supporting electronics; and/orwherein the overflow structure is in a sewer system; and/or furthercomprising determining fluid level trending information; and/or furthercomprising at least one of determining if there is an obstruction in theoverflow structure and removing rain effects from the trendinginformation.

In additional aspect of the disclosed embodiments, a combined overflowstructure (COS) detection system is provided, comprising: first meansfor determining a fluid level, positioned over an overflow structure todetermine a fluid level of a non-overflow side of the overflowstructure; second means for determining the fluid level, positioned overa top of a weir in the overflow structure; supporting electronics abovethe overflow structure and coupled to the first and second means;wireless transmitting means coupled to supporting electronics; a centraldata processing system receiving data from the wireless transmittingmeans; and from the received data, start and end time of an overflowevent and determining a volume of fluid discharged over the weir can bedetermined.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a related art illustration showing a conventional combinedsewer (CSS) structure.

FIG. 1B is a related art illustration showing the CSS of FIG. 1A in anoverflow state.

FIG. 2 is an illustration of an exemplary sensor use and/orconfiguration to monitor and detect overflow conditions.

FIG. 3 is block diagram showing connectivity and datacommunication/management options using the exemplary sensors shown inFIG. 2 .

FIG. 4 is an illustration showing various possible hardware componentsor functionality in an exemplary CSO sensor system.

FIG. 5A is a side view illustration of a weir overflow trigger sensordesign.

FIG. 5B is a perspective view illustration of a weir overflow triggersensor

FIG. 5C is a bottom view illustration of a weir overflow trigger sensordesign.

FIG. 6 is an illustration of an exemplary MEM (micro-electro-mechanical)sensor structure for overflow detection.

FIG. 7 is a sample plot of sensor water/fluid level heights over time,indicating a trend of rising water level.

FIG. 8 is a block diagram illustrating another connectivity and datacommunication/management configuration using multiple sets of sensors,for improved condition assessment.

FIG. 9A shows a complete plot with raw rain and level data.

FIG. 9B shows the data of FIG. 9A modified by rain filtering.

DETAILED DESCRIPTION

Most of the volume of sewer overflows in the U.S. comes from combinedsewer systems. The Environmental Protection Agency (EPA) says there areabout 860 communities in the U.S. with combined sewers. These combinedsewers were designed to pass raw sewage from the source to treatmentplants under dry weather conditions. However, under stormy conditionsrain water and/or snow melt will enter these combined systems via stormdrains and, depending upon the intensity of the precipitation, stormwater combined with raw sewage will overflow these underground systemsand flow directly into the environment. Also, treatment plants at thetermination of the combined sewers are typically not large enough tohandle the combined load of sewage and storm water.

The Clean Water Act of 1972 prohibits the discharge of sewage into theenvironment, and since the enactment of this law, local, regional andfederal regulators have been acting to compel sewer system operators to“clean up their act” and cease the discharges into the environment. Oneof the measures of interest to the regulators, and the public ingeneral, is how much sewage has been dumped into the environment, andwhen the dumping occurred. Until recently, this monitoring has been doneby manual and sporadic observation, reported on a nearly random basis byobservant citizens. Without an automated means to provide the starttimes, the stop times, the durations, and the volume of the overflows,the regulators have no visibility into the progress made by regulatoryedicts such as consent decrees, the operators get no feedback from theircapital and operational improvements, and the public has no idea howseverely combined sewer overflows (CSO) are affecting the environmentand local waterways.

In view of the above, various systems and methods are described thatprovide a heightened degree of monitoring as well as accuracy ofinformation in the context of CSO scenarios. For example, various uniquemeans are described to (a) automatically and remotely monitor CSOlocations and provide real-time data regarding start times, stop times,duration, and flow volumes of overflows that occur in these structuresand provide regulatory and public notification of these events; (b)detect changes on the sewer side of the CSO (versus not on the overflowside) before, during, and after rain events to determine how muchmaterial or debris has washed into the sewer system, over the weir (toboth gain information on trends associated with debris as a function ofrainfall, and also provide maintenance alerts to operators to cleansewers before the next rain event to maximize capacity and also minimizeoverflows that would be exacerbated by debris; and (c) provide apredictive tool for predicting the response of a combined (or separate)sewer collection system to a particular storm event, enabling mitigationactivities and public notification prior to an event, and also provide aprioritized means to plan for capital improvements that could reduce oreliminate overflows under specified conditions. Various illustrationsare now provided, describing exemplary embodiments in view of the above.

FIG. 1A is a related art illustration showing a conventional combinedoverflow structure (COS) 100 located in a sewer, with the dry weatherseptic sewer side 110, environmental flow side (e.g. ocean, river, lake,etc.) 120 and weir 130. For ease of explanation, the COS structure whenlocated in a sewer will be referred to as a combined sewer structure(CSS), understanding that the concepts described for the sewerembodiment can be replicated to non-sewer implementations (e.g., COS).The septic sewer side 110 may contain a channel withwater/sewage/effluent 115. This structure 100 utilizes the height of theweir 130 to prevent flow of the effluent 115 into the environmental flowside 120. It should be appreciated that FIG. 1 's configuration is onlyone of several possible configurations, but is shown here to demonstratethe purpose of the weir 130 as a fixed height barrier. Accordingly,other configurations and or shapes/designs for a CSS system areunderstood to be within the scope of this disclosure. Also, while side120 is described as the environmental flow side, it is understood thatit is sometimes referred to in literature as the overflow side.Therefore, use of either term may be made without loss of generality.

FIG. 1B is a related art illustration 150 showing the CSS 100 of FIG. 1Ain an overflow state. If an excess of water/fluid 117 (for example, froma heavy rain storm, or flood, etc.) exceeds the height of the weir 130,it will pass over the weir 130 into the environmental overflow side 120.Of course, if sewage is mixed with the excess fluid 117, then it will bedirected to the environment rather than the sewage treatment plant.

FIG. 2 is an illustration 200 of an exemplary sensor use and/orconfiguration to monitor and detect overflow conditions. Here, aplurality of sensors 210,215,230 are situated “in-line” with theirrespective detection zone. The sensors can use any means for leveland/or flow detection, non-limiting examples being ultrasonic, radar,capacitive, optical, standoff water level, immersed water level, weirtrigger level, contact (e.g., float), moisture, conductivity sensor(s),magnetic, MEMs, etc. Additional optional sensor capabilities can includetemperature, humidity, gas, radioactivity, sound, etc.

In addition to the three (3) sensors shown, in some embodiments, it maybe desirable to move one of the overflow sensors 210,230 to aboveenvironmental overflow side 120. Alternatively, it may be desirable toadd an additional sensor (not shown) to the environmental overflow side120. In non-trigger operation, one or more of the exemplary sensorscould be put into a reduced power mode to prolong battery life.

The combination of the various sensors provides sector-specificinformation as well as “amount” of overflow, versus the use of a singlesensor in the overflow side 120 or on the septic sewer side 110. Forexample, while sensor 210 can determine that an overflow is occurring,sensor 230 can be used to measure the height of the water going over theweir 130. This would be used to determine the volume of water going overthe weir 130, using anyone or more of well-known formulas. Underrelatively dry conditions sensor 215 can be used to determine either thelevel or flow of the wastewater for capacity planning and maintenanceoptimization purposes. Thus, the combination of these sensors providesboth dry weather and wet weather information, as well as “precise”amounts of overflow, in contrast to a simple determination that overflowhas occurred.

The ability to gauge the amount of overflow is a significant improvementin the industry, enabling planners to better determine modifications toindividual sewers or sewer lines in future upgrades and regulators theability to properly assess the amount of contaminant in the environment,for example. Additionally, this information is made available tooperators and engineers on a near real time basis, so that status anddecisions can be accomplished quickly. Further, this information can becombined with other independent measurements to allow for more complexdecisions and determination of cause and effect processes. The rapidityof data recovery also supports more rapid calibration of measurementswith field conditions.

FIG. 3 is block diagram 300 showing connectivity and datacommunication/management options using the exemplary sensors shown inFIG. 2 . For example, the CSO sensor system 310 could send sensor datavia link 313 to/from a wireless communication system 320 (either in theCSO sensor system 310 and/or or as a separate system). The wirelesscommunication system 320 would forward via link 323 the sensor data to aserver database system 330. The server database system 330 would operateon the sensor data and notify supervisor/user(s) 340 via link 343 anystatus or alerts, etc. that would be relevant to the informationgathered.

As indicated in the links 313, 323, 334, information may bebi-directional and exchanged to and from the various blocks. Forexample, a CSO sensor system 310 may trigger an overflow alert whichwould be eventually conveyed to user 340. User 340 may have the optionto request the CSO sensor system 310 to reset one or more of itssensors, or poll for a different sensor parameter, etc. Additionally, apublic alert, for example in real-time, could be automatically generatedfrom the user 340 or the server database system 330. One or more oflinks313, 323, 334 may use an established communication network, e.g., cellphone, satellite, wi-fi, etc.

FIG. 4 is an illustration 400 showing various possible hardwarecomponents or functionality in an exemplary CSO sensor system. For animplementation within a sewer system, the components may be supportedfrom a manhole cover, if situated in a manhole. The components arereferred to here as “modules” but generally describe a specifiedfunction and therefore the “modules” do not necessarily denote aseparate device or structure. In some embodiments, it may be desirableto have the modules individually partitioned as shown, however, in otherembodiments one or more of the modules (e.g., function) may be shared orperformed by a single device, thus reducing the “module” count.

Sensors 410, 411, . . . , 41N represent the set of sensors in a sewer.Sensor accumulator module 420 receives the data from the sensors andforwards to support electronics module 430, which is processed byprocessing unit module 440, and ultimately wirelessly transmitted fromwireless interface (and/or transmitter and/or transceiver) module 450via antenna 460. Power supply 435 provides power for the various modulesand may be a battery. In some embodiments, sensors 410, 411, . . . 41Nmay have their own power source, for example, a battery. Powerregeneration (solar, kinetic, heat, Seebeck effect, etc.) may be part ofthe system, according to design preference.

FIGS. 5A-C are side, perspective, and bottom view illustrations of aweir overflow trigger sensor design. One or more sensor structures 535are situated on top of weir 530. The sensor structures 535 could beU-shaped with feet 560 (optimally, secured to the weir top via drilling,weight, screwing, etc.) the sensor element 550 disposed therein. Thesensor element 540 may be a conductive sensor, detecting liquid, or someother water/fluid/measurement sensor. Of course, other shapes, forexample, T, inverted V, pyramidal, and so forth may be used, the exactshape being dependent on design preference. The height of the sensorstructures 535 may be varied, with the sensing element 550 eitherunderneath the top of the sensor structures 535 or actually on top ofthe sensor structures 535 or even on a side of the sensor structures535. If the individual heights of the sensing element 550 on the weir530 top is incrementally staged, different overflow heights can beobtained.

As it is possible for an individual sensor element 550 to be fouled frommaterials in the water, “group” verification of an overflow conditioncan be employed. Measurement from either the sewer side sensor (notshown) or overflow sensor (not shown) would assist in determining if allsensor elements 550 are fouled. (E.g., no increase in height on thesewer side or overflow sensor when all sensor elements 550 signaloverflow would indicate complete fouling.) All fouled condition could bereported to the maintenance crew.

Not shown in the illustrations but implicit is their respectiveconnection to the sensor accumulator or supporting electronics, seen forexample in FIG. 4 . In some embodiments, the sensor elements 550 (orsensor structures 535) may be connected to each other, eithermechanically (for structural support) or electrically (for sensordata/power sharing).

FIG. 6 is an illustration of an exemplary MEMs(micro-electro-mechanical) sensor structure 600 to determine if there iswater flow over the weir (not shown). The MEMs sensor structure 600comprises a support frame 610, with an optional swiveling/rotatingattachment 620 that allows coupled MEMs sensor 630 to rotate, as needed.A float 640 is supplied at the bottom of the MEMs sensor 630 that raiseswhen “water” levels are above the weir, triggering a response from theMEMs sensor 630. The float 640 can also operate to “tum on” the MEMssensor 630, if so configured, thus reducing power consumption until atrigger event occurs. The actual location and position of the float 640can be a design choice, therefore, the float 640 may be positioned at adifferent position than shown. The MEMs sensor 630 may be programmed orcalibrated by the supporting electronics (See FIG. 4 ). A series ofthese devices could be mounted on the weir. This embodiment couldoperate in a similar manner to the conductive sensor embodimentdescribed in FIGs. SA-C.

In some embodiments, the exemplary CSO/overflow sensors and/or systemmay be self-monitoring in terms of power supply, communications, andsensor performance and can be designed to send a notification ofanomalies to an operator (either directly from the CSO system or to anend user/supervisor). Additionally, operation of one or more of thevarious sensors may be enabled, turned on, turned off, varied dependingon weather or power consumption conditions. For example, turn on and/orincreased sampling may be triggered if a rain or flood is expected. Or,upon detection of increased fluid levels, an initially slow sample ratemay be increased to give more timely updates for increased accuracy.

In addition to overflow detection, the exemplary configuration ofsensors allow for debris detection. That is, in a non-rain/floodscenario, a sudden increase of height of the sewer side or overflow sideis indicative of debris. Or after a rain/flood, the persistence ofincreased height will indicate accumulated debris, requiring attentionfrom maintenance operators. These conclusions are not only possible fromsingle event determination by comparing sensors with weather data, butalso determinable from trending information from the sensors. That is,“regular” flow can be used as a baseline for trending information withthe understanding that “regular” flow will have troughs and peaks,wherein a sustained peak is indicative of debris accumulation in theflow path. Debris accumulation can also be indicated by gradual rise(i.e., trending) of the trough, wherein sediment can be the constituentdebris or small bits of debris. Noting such conditions will flag theseCSOs as candidates for possible overflow in a rain/flood event, whereinmaintenance can be tasked to clean these CSOs prior to the weatherevent.

Elaborating further, combined sewer systems, because they take in stormwater, can collect a large amount of debris during storm events. Withoutmanual inspection of these sites, the amount of debris, silt, etc.accumulating at a particular site is unknown. When the next stormarrives, locations that are meant to flow storm and sewage water to thetreatment plant can be blocked and the untreated overflow can easilyexceed what would be expected with an unblocked diversion or controlstructure. Aspects of this approach are detailed in U.S. Pat. No.9,297,684 and U.S. patent application Ser. No. 14/017,280, by theinstant inventors and is incorporated herein for their teachings.

FIG. 7 is a sample plot 700 of sensor water/fluid level heights overtime, indicating a trend of rising water level (both in troughs andpeaks), as revealed from the overall period of time. Water level trendscan be measured using fast Fourier transform (FFT) analysis, or leastsquares fitting of data to a polynomial, or other techniques. Undernon-rain conditions, the water level measurements at a CSO structure, byone or both of the sensors that are on the dry/sanitary side of thestructure can be used to determine that there is buildup by noting therise of water levels and inability to retreat back to normal levels.

FIG. 8 is a block diagram 800 illustrating another connectivity and datacommunication/management configuration using multiple sets of sensors,for improved condition assessment. For example, sensor set 811, 812, . .. , 81N are in communication with a Remote Field Unit (RFU) 825 that islocated in a sewer system. The RFU 825 relays the sensor information toa database/server 830, which also is in communication with another setof sensors 885. One or more of sensors 885 may augment the informationprocessed by database/server 830 for increased knowledge and betterdecision making. For example, sensors 885 may forward geographicallyrelevant environmental information such as snow melt, tides, rain fall,temperature, gas (e.g., H_(s)S, CI₂, CO, CO₂, O₂, aromatic hydrocarbons,etc.) humidity, wind, etc. These sensors may be “external” to the sewersensors 811, 812, . . . 81N and would give an extra layer of informationfor appropriate condition assessment. For example, one or more ofsensors 885 may detect hydrocarbons therefore an increase in fluid levelfrom sewer sensors 811, 812, . . . 81N may indicate gasoline or oilentering the sewer weir. Similarly, one or more sensors 885 may beinterior to the sewer but not at a weir and therefore, provide similarinformation—that gasoline/oil is entering the sewer, but not yet at aweir. In extension, run-off from chemical or mineral deposits can bedetected, for example run-off from an iron ore deposit may leak into thesewer.

The “external” sensors 885 would enable machine learning or heuristiclearning to observe the response of the CSS to various outsideinfluences. Once a response is measured, predictions of the system as afunction of outside influences could be made. The ability to predict theeffects of an external event on the internal sewer system is invaluableas it provides advance notice to maintenance crews and the managers, soremedial action can be timely initiated or harm can be mitigated.

FIGS. 9A-B are plots showing trends that can be biased by the responseof the CSO structure during and after rain events. FIG. 9A shows acomplete plot with raw rain and level data. There are two possibleapproaches to “normalizing” the rain event data to extract trendingdata. One approach is to blank out (remove) the level data during andfor a fixed time after the rain ceases (or reaches a specified lowrate—for example, 4 hours). The other approach is to blank out raw raindata to isolate that measurement from the long term trends in the sewer.The threshold amount could be zero or a fixed value, or variabledepending on the behavior of the site and/or based on historical levelsin response to previous/similar rain events. As an example, FIG. 9Bshows the data of FIG. 9A modified by filtering during and after rainevents, until levels return to a lower, threshold state. Rain events canforce transient excursions of water level that are not characteristic ofthe long term trends in the sewer. It is assumed that, in some cases, ahigher quality of decisions can be made by ignoring the transient eventsand replacing that data with either zero values, or by the mean valuewithin a processing window.

It should be noted that while the above description is presentedexpressly in the context of a combined sewer system, other systems wherea combination of materials with an overflow section may benefit from thesystem described herein. Therefore, these embodiments may be applied(with appropriate modifications) to enclosures, channels that requiresome measure of flow/volume overflow determination. Accordingly, it isunderstood that various modifications and changes may be made to thesystems and methods described above to render them applicable to otherfields, without departing from the spirit and scope of this disclosure.

It is noted that the functional blocks, methods, devices and systemsdescribed in the present disclosure may be integrated or divided intodifferent combinations of systems, devices, and functional blocks, aswould be known to those skilled in the art. In general, it should beunderstood that the hardware described herein could use integratedcircuit development technologies, or via some other methods, or thecombination of hardware and software objects could be ordered,parameterized, and connected a software environment to implementdifferent functions described herein. For example, algorithm-basedfeatures of the present application may be implemented using a generalpurpose or dedicated processor running a software application throughvolatile or nonvolatile memory constituting non-transitory signals.Also, the hardware objects could communicate using non-transitoryelectrical signals, with states of the signals representing differentdata.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopebeing indicated by the following claims.

What is claimed is:
 1. A combined overflow structure (COS) detectionsystem, comprising: a sensor set operably configured over an overflowstructure, comprising: a first module of the sensor set, operablydirected over a non-overflow side of the overflow structure to determineat least one of a fluid level and fluid characteristic of fluid on thenon-overflow side; a second module of the sensor set, operably directedover a top of a weir of the overflow structure to determine at least oneof a fluid level and fluid characteristic of fluid over the top of theweir sensor supporting electronics coupled to the sensor set; a wirelesstransmitter coupled to the sensor supporting electronics; and an antennacoupled to the wireless transmitter; a central data processing systemreceiving data from the sensor set, wherein the data is used todetermine at least one of a start time, end time of an overflow eventand volume of fluid discharged over the weir.
 2. The detection system ofclaim 1, further comprising a third module of the sensor set, coupled tothe sensor supporting electronics, and operably directed over anoverflow side of the overflow structure to determine a fluid level ofthe overflow side.
 3. The detection system of claim 1, wherein theoverflow structure is in a sewer system.
 4. The detection system ofclaim 3, wherein the overflow structure is in a manhole.
 5. Thedetection system of claim 1, wherein one or more of the modules areeither ultrasonic, radar, capacitive, optical, standoff water level,immersed water level, weir trigger level, contact, float, moisture,conductivity sensor, magnetic, or micro-electro-mechanical (MEM).
 6. Thedetection system of claim 1, wherein a first data from the first moduleand a second data from the second module provide two separate fluidlevel measurements, one for non-overflow conditions and one in foroverflow conditions.
 7. The detection system of claim 1, furthercomprising one or more external sensors forwarding data to the centraldata processing system.
 8. The detection system of claim 7, wherein theone of more external sensors is a rain sensor.
 9. The detection systemof claim 8, wherein historical or trending data from the rain sensor anddata from the sensor set is used to establish a rain mask and non-rainmask.
 10. The detection system of claim 9, wherein at least one of arain mask and non-rain mask is used to distinguish between a rainrelated event and a blockage related event.
 11. The detection system ofclaim 1, wherein power for the sensor set, modules, sensor supportingelectronics and the wireless transmitter is from at least one of abattery, solar, kinetic, heat, and Seebeck effect power source.
 12. Thedetection system of claim 1, wherein the sensor set is self-monitoringand the system sends a notification of an anomaly to a pre-determinedperson.
 13. The detection system of claim 1, wherein the system sends amaintenance notification for the overflow structure to a pre-determinedperson.
 14. The detection system of claim 1, wherein the data is furtherutilized to properly assess an amount of contaminant present.
 15. Thedetection system of claim 1, wherein one or more of the modules istemporarily powered down.
 16. The detection system of claim 1, wherein asampling rate of the data is variable.
 17. The detection system of claim1, wherein a level of silt in the overflow structure is determined. 18.A combined overflow structure (COS) detection system, comprising: asensor system operably configured over an overflow structure, wherein afirst sensor of the sensor system measures a non-overflow side of theoverflow structure to determine at least one of a fluid level and fluidcharacteristic of fluid on the non-overflow side, and wherein a secondsensor of the sensor system measures a top of a weir of the overflowstructure to determine at least one of a fluid level and fluidcharacteristic of fluid over the top of the weir, sensor supportingelectronics coupled to the sensors, operating differently for at least anon-overflow and overflow condition; a wireless transmitter coupled tothe sensor supporting electronics; and an antenna coupled to thewireless transmitter; and a central data processing system receivingdata from the sensors, wherein the data is used to determine at leastone of a regular flow level for the non-overflow condition and astart-stop, duration for an overflow condition.
 19. A method foroverflow detection in an overflow structure (COS), comprising:positioning a sensor set operably configured over an overflow structure,wherein a first module of the sensor set is directed over a non-overflowside of the overflow structure to determine at least one of a fluidlevel and fluid characteristic of fluid on the non-overflow side, and asecond module of the sensor set is directed over above a top of a weirof the overflow structure to determine at least one of a fluid level andfluid characteristic of fluid over the top of the weir; coupling sensorsupporting electronics above the overflow structure to the sensor set;coupling a wireless transmitter to the sensor supporting electronics;coupling an antenna to the wireless transmitter; transmitting sensordata to a central data processing system; and establishing at least oneof a start time, end time of an overflow event and volume of fluiddischarged over the weir.
 20. The method of claim 19, furthercomprising, determining fluid level trending information.
 21. The methodof claim 19, further comprising, from historical or trending data,creating at least one of a rain mask and non-rain mask.
 22. The methodof claim 20, further comprising, distinguishing between a rain relatedevent and a blockage related event using the rain mask and non-rainmask.
 23. The method of claim 19, further comprising, sending anotification of an anomaly to a pre-determined person.
 24. The method ofclaim 19, further comprising, sending a maintenance notification for theoverflow structure to a pre-determined person.